Just as the Rev. Martin Luther King Jr. led the Montgomery Bus Boycott at age 26, and Rep. John Lewis helped to lead freedom rides at 23, young Americans are not letting age get in the way as they seek more than a contributing role in the push for social reform.

Tens of thousands of people marched to the Martin Luther King Jr. Memorial and down the National Mall on Saturday, commemorating the 50th anniversary of King’s famous speech and pledging that his dream includes equality for gays, Latinos, the poor and the disabled.

Next week, the nation’s first black president, a living symbol of the racial progress Martin Luther King Jr. dreamed about, will stand near the spot where King stood 50 years ago and say where he believes this nation should be headed.